The computer management of perpetual inventory is a common process today. There are many methods for tracking who takes, returns or restocks items in a store room or warehouse in order to maintain a record of the on-hand quantity, and to monitor that quantity in order to place orders to replenish stock. A typical system comprises a computer with a database storing information about each item, and means for users to interact with that database, to maintain a computer based numerical representation of what is actually physically on the shelves. The maintenance of the information in the computer can be as simple as requiring a user interacting with the inventory, to subsequently go to a nearby computer terminal, and input information about what they did. For busy stock rooms, and particularly large warehouses, having a fixed terminal entry requiring multiple users to remember or note down what they did at multiple item locations, and return to a fixed location to enter data into a computer terminal, is at best inconvenient, and at worst will be a process that users are unlikely to consistently follow. The same is true of a supervisor's maintenance functions, such as assigning or de-assigning an item to a location, entering the maximum and minimum levels required, and performing routine check functions such as Physical inventory counting (a.k.a. Cycle Counting). All these operations need to be done at the location where the item is located on a shelf or in a bin, physically remote from any fixed computer terminal(s).
There are a number of ways in which the problem of multiple users taking and returning items, and supervisors maintaining items, have been solved when the item locations are remote from a computer terminal. One has been to use portable intelligent bar code scanners that communicate with the base computer and where information can be entered on the scanner screens. One of the issues with this method is that portable devices have a tendency to get stolen or mislaid. Another is such devices are expensive and require special programming and maintenance. An alternative method is described here using wirelessly connected button modules, and the invention described is intended provide improvements on this method.